Shoes for Walking Really Fast

From August '96 Walking Magazine

According to walking instructor Bonnie Stein of Tampa, FL, 95% of the
people who start her racewalking classes are wearing inappropriate
footwear--which is shocking since most are wearing "walking" shoes.
Unfortunately, they're often the classic all-leather variety, perfect for
moderate-speed fitness walking, but ultimately built more for durability than
speed. And in Bonnie's classes, you're bound to eventually get going pretty
fast--5 mph or more. So she recommends looking for fast walking shoes that fit
the following bill:

Very lightweight and breathable

Extremely flexible at the ball of the foot (you don't have to work to
bend them)

A wide toebox (for comfort as the foot flexes)

A low heel (for the walking heel-strike) with durable cushioning

Shoes from several different categories may suffice, including walk/run
shoes, racewalking shoes, and even some lightweight running shoes, called racing
flats. (these tend to have lower heels and more flexibility than most running
shoes, making them much like their run/walk cousins.) Here are a few models that
walkers in Bonnie's classes recommend: